Magnetic field generator and detector position indicator

• US 5,434,500 A
• Filed: 07/26/1993
• Issued: 07/18/1995
• Est. Priority Date: 07/26/1993
• Status: Expired due to Fees

• Current Assignee: Bruce Hauck, Gwynn Holbrook
• Original Assignee: Bruce Hauck, Gwynn Holbrook
• Inventors: Hauck, Bruce, Holbrook, Gwynn
• Primary Examiner(s): Strecker, Gerard R.
• Application Number:
  US08/096,308
• Time in Patent Office: 722 Days
• Field of Search: 324/67, 324/207.17, 324/207.26, 324/258, 324/260, 324/326, 324/529
• US Class Current: 324/67
• CPC Class Codes: G01B 7/003 for measuring position, not involving coordinate determination coordinate measuring G01B7/004
• CPC Class Codes: G01V 3/081 the magnetic field is produced by the objects or geological structures characterised by the method of magnetic field measurement G01R33/00

Abstract

A device for determining a position by locating a point on one side of a barrier such as a wall from the other side of the barrier has two main parts, a magnetic field generator (sending unit) and a receiver (receiving unit) which is able to detect the magnetic field. The sending unit, which is placed on the first side of the wall at the spot to be located, creates a magnetic field at that spot. The receiving unit is composed of two pairs of detectors (four detectors total) which measure the relative strength of the magnetic field at each detector. Measurement of the relative strength of the magnetic field at each detector allows the position of the source to be determined. The strength of the field is indicated by the display of light emitting diodes. When the strength of the field is equal at all four points the receiving unit is centered directly on the opposite side of the wall from the sending unit.

Claims

1. A position locator comprising:

sending unit means for generating a magnetic field from an alternating current source, the sending unit means comprising a casing having a front end;

a coil positioned within the front end of the casing;

a switch in electrical communication with the coil; and

a plug in electrical communication with the switch, whereby the plug can be engaged to an alternating current power source to permit alternating current to flow through the coil to generate a magnetic field radiating therefrom;

a magnetic field detecting means for detecting a magnetic field generated by the sending unit means and for indicating a position of the magnetic field detecting means relative to the sending unit means, the magnetic field detecting means comprising a substantially square main body having four corners with a first coil mounted to the main body proximal to a first corner thereof, a second coil mounted to the main body proximal to a second corner diagonally opposite the first corner, a third coil mounted to the main body proximal to a third corner thereof, and a fourth coil mounted to the main body proximal to a fourth corner diagonally opposite the third corner of the main body;

a first comparator means in electrical communication with the first coil and the second coil for generating a first comparative signal corresponding to a voltage output of the first coil relative to a voltage output of the second coil;

a first AND gate means in electrical communication with the first comparator means for generating a first AND gate signal corresponding to the voltage output of the first coil relative to the voltage output of the second coil;

a first LED means in electrical communication with the first AND gate means and electrically communicable with a power source for illuminating when the voltage output of the first coil is substantially higher than the voltage output of the second coil;

a second AND gate means in electrical communication with the first comparator means for generating a second AND gate signal corresponding to the voltage output of the first coil relative to the voltage output of the second coil;

a second LED means in electrical communication with the second AND gate means and electrically communicable with a power source for illuminating when the voltage output of the second coil is substantially higher than the voltage output of the first coil;

a second comparator means in electrical communication with the third coil and the fourth coil for generating a second comparative signal corresponding to a voltage output of the third coil relative to a voltage output of the fourth coil;

a third AND gate means in electrical communication with the second comparator means for generating a third AND gate signal corresponding to the voltage output of the third coil relative to the voltage output of the fourth coil;

a third LED means in electrical communication with the third AND gate means and electrically communicable with a power source for illuminating when the voltage output of the third coil is substantially higher than the voltage output of the fourth coil;

a fourth AND gate means in electrical communication with the second comparator means for generating a fourth AND gate signal corresponding to the voltage output of the third coil relative to the voltage output of the fourth coil; and

a fourth LED means in electrical communication with the fourth AND gate means and electrically communicable with a power source for illuminating when the voltage output of the fourth coil is substantially higher than the voltage output of the third coil, whereby the sending unit means can be positioned on a first side of a wall, with the magnetic field detecting means being positionable on a second side of the wall, wherein the LED means of the magnetic field detecting means cooperate to indicate a position of the magnetic field detecting means relative to the sending unit means.

2. The position locator of claim 1, wherein the main body is shaped so as to define a hole extending therethrough centered between the first coil, the second coil, the third coil, and the fourth coil for permitting a passage of a marking means therethrough for marking a wall against which the main body is positionable.